Detailing the Dispositional Theory of Desire

In our last exciting episode, I provided a brief account of the Dispositional Theory of Desire and some preliminary arguments against it.

The dispositional account says (according to the Stanford Encyclopedia of Philosophy entry on "Desire":

For an organism to desire p is for the organism to be disposed to take whatever actions it believes are likely to bring about p.

The arguments against this were:

Explaining and predicting the behavior of agents with multiple desires would be extremely complex. It would require specifying all of the conditions under which any combination of desires would outweigh any other combination of desires. This becomes much simpler if we view motivation like vectors, having a direction and a magnitude. However, associating a magnitude (strength) to a desire takes the theory out of the dispositional account and into the evaluativist account.

Many common dispositions to act - such as those represented by habit and Turret syndrome - are not, in fact, associated with desires. This is mainly because the agent does not attach any importance to the act or its consequences.

However, dispositional theories contain an important truth - desires motivate action. Desires create dispositions to act. However, the relationship between the desire and disposition is not one of identity (a desire is a disposition to act), it is one of cause and effect (desires cause dispositions to act).

Among philosophers, the discussion of the case of Radioman, which Warren Quinn presented in Quinn, Warren 1993: ‘Putting Rationality in its Place’ in his Morality and Action (Cambridge: Cambridge University Press).

Radioman has a disposition to turn on radios. If he is in the vicinity of a radio that is not on, he is disposed to reach out and turn them on. He does not do this because he has some interest in the results of turning on radios. He does not want to listen to music and, in fact, would prefer the silence. Nor does he care about turning on radios as an end in itself. He doesn't care about anything - he just performs the action.

The conclusion is that this is the case in which "Radioman is disposed to turn on radios" is true, and "Radioman has a desire to turn on radios" is false, which disproves the thesis that being disposed to act is the same as having a desire to act.

As a rule, I don't like this type of thought experiments. We invent language as a tool to use in everyday circumstances. We can well imagine novel situations and wonder what to say about them. Our normal language doesn't fit, so we tend to stretch concepts. It is a mistake to think that these contortions and distortions indicate something significant.

Indeed, this figures into Michael Smith's response to Quinn's radioman.

Smith, Michael (2012), "Four Objections to the Standard Story of Action (and Four Replies):", Philosophical Issues, 22, Action Theory,, pp 387-401.

Smith wants to call Radioman's disposition to turn on radios a desire.

[W]e know something both distinctive and familiar about the origins of Radioman’s behaviour. We know that he has an urge to turn on radios, and we know that whether his urge will have any effect at all will depend on two things. First of all, it will depend on whether he has stronger contrary dispositions: imagine telling him that if he turns on a radio you will shoot him in the head, so bringing his urge into conflict with his desire to preserve his life. And second, it will depend on what options he believes will bring about the thing that he has an urge to do: that is, it will depend on whether he believes that there are radios in the vicinity whose operations he can affect by his bodily movements.

These assumptions certainly make it appear that Radioman's behavior counts as desire-driven, particularly given his capacity to decide not to turn on radios if his life is threatened.

However, will he refrain from turning on radios if his life is threatened? Perhaps he will not - but he will if his child's life is threatened. Perhaps he will refrain if he is paid $1000 but not if he is paid $10. What about $199.95?

In Smith's response, he is assuming that Radioman assigns a certain value or importance to turning on radios. There is a price at which he will refrain from doing so, indicating that, below this point, turning on radios has more value than the money and, above this point, the money has more value than turning on radios. I would suggest that this assignment of a value is exactly what Quinn's objection was getting at - this is the missing element in a dispositional account of desire. By assigning a value to turning on radios, Smith doesn't answer Quinn's objection. He surrenders to it.

However, we do not need to invent counter-examples and distort and stretch concepts beyond everyday usage to come up with an objection to the dispositional theory. We can look at a category of actual real-world behavior that qualifies as "dispositions to act" but not as "desire". These are habits.

For 12 years, when I left work at the end of the day, I would leave the building and turn right to go to the bus station. Then the city built a new bus station (it is difficult to build an old bus station) a few blocks to the left. When the new bus station opened, they closed the bus station to the right. Yet, quite a few times, I left the building where I worked and turned right. I then walked down the street for a while, then turned around and went in the other direction.

I had a disposition to turn right as I left the building, but I did not have a desire to turn right. It was not something I valued for its own sake, nor was it something that I valued as a means to an end. It would be a mistake to say that I believed that the bus station was to the right because, if anybody had asked me, I would have reported that the bus station was closed and the new bus station was three blocks away to the left. So, I did not turn right as a result of means-ends rationality. I had a disposition to act that was not, in any way, associated with a desire.

Yet, it was still an intentional action. Turning right was as intentional as turning left would have been. Turning right was as intentional the first day after the old bus station closed as it was the last day the old bus station was still open.

This gives us a real-world example of Radioman.

And, indeed, as I left the building, if somebody had threatened to shoot me in the head if I had turned right upon leaving the building I would have likely put extra effort into making sure that I turned left. I would have turned left anyway. That is what I wanted to do. That was where I was going to find the bus that would take me home.

So, we do not need to invent some strange story of a person who has a disposition to act who does not have a desire - an example that shows that "a desire is a disposition to act" is false. We have real-world examples we can draw from. This gives us reason to deny the proposition that a desire is a disposition to act.